1. Field of the Invention
The present invention relates generally to and particularly to optical waveguide telecommunications, optical amplifiers and optical waveguide devices.
2. Technical Background
The present invention relates generally to optical telecommunications systems, and more particularly to optical waveguide devices utilized in optical telecommunications systems.
Optical telecommunications systems consist of multiple operation stations spaced distances apart. Usually the operation stations are separated by a distance of several kilometers and are connected together with optical fibers. The main purpose for constructing an optical telecommunications systems is usually to communicate information in an optical format over long distances that exceed the distances separating neighboring operation stations in the system. In addition to communicating such information to entities or subscribers outside of the system, the complexity of optical telecommunications now requires that information be communicated within the system and between the operation stations to insure proper service, maintenance and operation of the system. Within the system such information is communicated between the stations using optical service channels. Optical service channels can for example allow human operators at the stations to talk to each other without accessing the wavelength channels used to transmit information to points outside the system. Additionally optical service channels can be used to control automated components such as computers and related attachments at a station from another distant station or central operations location. Optical service channels also relay service and maintenance information to the stations so that the system operates smoothly and avoids malfunctions which could interrupt service through the system.
Optical amplifiers are important components used in such optical fiber telecommunications systems and are part of the ever growing complexity of the system that has made optical service channel communications a benefit for such systems. Optical signals transmitted in optical fibers tend to weaken as they travel along the optical fibers. Optical amplifiers provide an economic means of amplifying such weakened optical signals while maintaining the optical nature of the signal, thus allowing communications over long distances.
Erbium doped optical fiber amplifiers have become the dominant means of amplifying optical signals in the 1550 nm optical telecommunications window. Such erbium doped optical fiber amplifiers are normally directly pumped with 980 nm and/or 1480 nm semiconductor pump lasers. With such an amplifier-pump system, electrical energy applied to the 980 nm (1480 nm) semiconductor pp laser produces 980 nm (1480 nm) photons which are coupled through an optical fiber pigtail into the erbium doped optical fiber. The 980 nm and/or 1480 nm pump light excites/energizes the erbium ions in the erbium doped optical fiber so that 1550 nm optical telecommunications signals are amplified by the excited/energized erbium ions.
The optical amplifier and optical telecommunications industry needs a technology which allows for proper operation of the optical amplifiers and allows for the communications of beneficial optical service information.
One aspect of the present invention is an optical waveguide optical amplifier device for use with an optical telecommunications system that transmits optically amplifiable subscriber channels and communicates service information internally within the system with optical service channels and includes an optical amplifier input, an amplifier output, and optical amplifier medium. The optical amplifier input includes a reflective isolator longitudinal body with a first end and a second end. The first end includes an input fiber receiving the subscriber and optical service channels inputted into the amplifier input and an output fiber transmitting the subscriber channels to the amplifier medium. The second end of the reflective isolator body includes an optical service channel accessor which guides the subscriber channels to the output optical fiber. The amplifier device further includes an optical service channel receiver connected to the optical service channel accessor such that an optical service channel that enters the reflective isolator body from the input fiber is transmitted through the optical service channel accessor to the receiver and away from the output fiber.
In another aspect, the present invention includes a multi-channel optical amplifier for a telecommunications system that transmits at least eight separate optically amplifiable subscriber channels to the exterior of the system and communicate internally desirable service information for the system with at least one optical service channel within the system. The amplifier includes an amplifier input, an amplifier output, and an amplifier medium positioned between the amplifier input and the amplifier output, the amplifier medium optically amplifying the at least eight subscriber channels; and an optical service channel receiver receiving the optical service channel information. The amplifier input includes a reflective isolator body with a first end and a distant opposing second end. The first end includes an input optical fiber and an output optical fiber proximate the input fiber. The input fiber receives the at least eight subscriber channels and the optical service channel, and the output fiber outputs and guides the at least eight subscriber channels to the amplifier medium. The second end of the isolator body includes an optical service channel accessor which guides the optical service channel away from the first end and to the optical service channel receiver and also guides the at least eight subscriber channels back to the first end and into the output fiber.
In a further aspect, the present invention includes a optical waveguide telecommunications device for use with a dense multi-channel communications system which transmits subscriber data via optically amplifiable subscriber channels and utilizes a desired optical service channel different from the subscriber channel to communicate service information desired internally within the system. The device includes a reflective isolator longitudinal body with a first end and a digital opposing second end. The first end includes an input fiber and an output fiber adjacent to the input fiber. The second end includes an optical service channel accessor which transmits the optical service channel through the second end and away from the first end, and diverts all light outside of the optical service channel back to the first end. The device includes an optical service channel optical coupler adjacent and integral with the second end. The optical service channel optical coupler couples the optical service channel from the accessor to an optical service channel receiver pigtail waveguide.
The invention further includes a method of making an optical waveguide optical amplifier for use with a telecommunications system that transmits subscriber channels and communicates service information within the system with an optical service channel. The method includes: providing an amplifier output outputting subscriber channels, providing an amplifier medium amplifying the subscriber channels, coupling the output to the amplifier medium, providing an optical service channel receiver receiving the optical service channel, and providing an amplifier input. The step of providing an amplifier input includes providing a reflective isolator body having a first end and a second end, the first end including an input optical fiber for receiving the subscriber channels and the optical service channel, and an output fiber for transmitting the subscriber channels to the amplifier medium. The second end includes an optical service channel accessor which transmits the optical service channel to an optical service channel waveguide and guides the subscriber channels to the output fiber at the first end. The method further includes the step of coupling the output fiber to the amplifier medium and coupling the optical service channel waveguide to the optical service channel receiver.
Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein, including the detailed description which follows, the claims, as well as the appended drawings.
It is to be understood that both the foregoing general description and the following detailed description are merely exemplary of the invention, and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the invention, and together with the description serve to explain the principles and operation of the invention.